Passive entry and passive start (PEPS) systems for vehicles have been proposed that rely on a manual wake-up action such as touching or pulling on a door handle to wake-up the system. Such a configuration may lead to a so-called ‘wall effect’ that caused a brief, but possibly annoying, delay between the manual wake-up action and a vehicle door being unlocked by the PEPS system resulting in the operator attempting to open a locked door. Another configuration has been proposed where the vehicle emits an interrogation signal, or a nomadic device (e.g. a PEPS key fob) emits an activation signal, at regular intervals so the wake-up of the PEPS system is performed as an operator carrying the nomadic device approaches the vehicle. However, this configuration leads to an undesirable energy drain on either the vehicle battery or the nomadic device battery, depending on the PEPS system configuration. What is needed is a relatively long range trigger that initiates nomadic device/vehicle communications without a significant drain on nomadic device or vehicle batteries.